| ACA | A Chartered Accountant 
| Others |
| ACA | A Cut Above
| Others |
| ACA | Abarth Club America
| Others |
| ACA | Abbreviations com American
| Others |
| ACA | Academic Cooperation Assocation
| Others |
| ACA | Academics Community and Athletics
| Others |
| ACA | Academy of Certified Archivists
| Others |
| ACA | Acapulco, Mexico
| Others |
| ACA | Accela Citizens Access
| Others |
| ACA | Access Control Agent
| Others |
| ACA | Accreditation Council for Accountancy
| Others |
| ACA | acetoacetate
| Others |
| ACA | Acquired Child Aphasia
| Others |
| ACA | Acrodermatitis Chronica Atrophicans
| Others |
| ACA | Acrolein Cyanohdryinacetate An
| Others |
| ACA | Active Cornering Assist
| Others |
| ACA | Actual Cost Adjustment
| Others |
| ACA | Acute Cerebellar Ataxia
| Others |
| ACA | Acute Cutaneous Anaphylaxis
| Others |
| ACA | Adaptive Channel Allocation
| Others |
| ACA | Adaptive Component Architecture
| Others |
| ACA | Adaptive Computing Architecture
| Others |
| ACA | Adaptive Conjoint Analysis
| Others |
| ACA | Adaptive Cruise Assistant
| Others |
| ACA | Address Control Application
| Others |
| ACA | adenylyl cyclase A
| Others |
| ACA | Adjacent Channel Attenuation
| Others |
| ACA | Adobe Certified Associate
| Others |
| ACA | Adrenal Cortex Autoantibodies
| Others |
| ACA | Adult Children Anonymous
| Others |
| ACA | Adult Children of Alcoholics
| Others |
| ACA | Advance Cargo Advice
| Others |
| ACA | Advanced Cargo Aircraft
| Others |
| ACA | Advanced Collision Avoidance
| Others |
| ACA | Adventure Cycling Association
| Others |
| ACA | Aerospace Consultancy Associates
| Others |
| ACA | Affordable Care Act
| Medical |
| ACA | Africa Capacity Alliance
| Others |
| ACA | Afro Caribbean Association
| Others |
| ACA | After Contract Award
| Others |
| ACA | Agence Coloniale Automobile
| Others |
| ACA | Agence Commerciale Automobile
| Others |
| ACA | Agence Conseil Automobile
| Others |
| ACA | Agency for Cultural Affairs
| Others |
| ACA | Agent Character
| Others |
| ACA | Agricultural Crop Additive
| Others |
| ACA | Air Commerce Act
| Others |
| ACA | Airborne Collection Assembly
| Others |
| ACA | Airlift Clearance Authority
| Others |
| ACA | Airspace Control Authority
| Others |
| ACA | Airspace Coordination Area
| Others |
| ACA | Alabama Christian Academy
| Others |
| ACA | Alberta College of Art (part of SAIT and prior to 1960 part of PITA)
| Others |
| ACA | All Correspondence Answered
| Others |
| ACA | Alley Cat Allies
| Others |
| ACA | Alliance of Criminal Activities
| Others |
| ACA | Allied Control Authority
| Others |
| ACA | Allstates Certificate Advantage
| Others |
| ACA | Almost a Chartered Accountant
| Others |
| ACA | Alpine Club Alsace
| Others |
| ACA | Alpine Cote d'Azur
| Others |
| ACA | Always Cancelled Airplanes
| Others |
| ACA | Amateurs de Citroen Anciennes
| Others |
| ACA | Amazon Conservation Association
| Others |
| ACA | America, Canada, and Australia
| Others |
| ACA | American Cable Association
| Others |
| ACA | American Camaro Association
| Others |
| ACA | American Camp Association
| Others |
| ACA | American Camping Association
| Others |
| ACA | American Canine Association
| Others |
| ACA | American Canoe Association
| Others |
| ACA | American Canyoneering Academy
| Others |
| ACA | American Canyoneering Association
| Others |
| ACA | American Car Audio
| Others |
| ACA | American Chichlid Association
| Others |
| ACA | American Chiropractic Association
| Others |
| ACA | American Citizens Abroad
| Others |
| ACA | American Coatings Association
| Others |
| ACA | American College of Apothecaries
| Others |
| ACA | American Communication Association
| Others |
| ACA | American Compliance Association
| Others |
| ACA | American Correctional Association
| Others |
| ACA | American Corvette Association
| Others |
| ACA | American Counseling Association
| Others |
| ACA | American Country Awards
| Others |
| ACA | American Cryptogram Association
| Others |
| ACA | American Crystallographic Association
| Others |
| ACA | aminocaproic acid
| Others |
| ACA | Amoskeag Company A
| Others |
| ACA | Amputee Coalition of America
| Others |
| ACA | Anchorage Corvette Association
| Others |
| ACA | Andres Castro Arms
| Others |
| ACA | Angel Capital Association
| Others |
| ACA | Anhydrous Codeine Alkaloid
| Others |
| ACA | Animal Charities of America
| Others |
| ACA | Animated Cel Archive
| Others |
| ACA | Anisotropically Conductive Adhesive
| Others |
| ACA | Another Confusing Acronym
| Others |
| ACA | Anterior Cerebral Artery
| Others |
| ACA | Anterior Communicating Artery
| Others |
| ACA | Anti Copyright Association
| Others |
| ACA | Anti Corruption Agency
| Others |
| ACA | Anti-Cardiolipin Antibody
| Others |
| ACA | Anti-Centromere Antibody
| Others |
| ACA | Anti-Corruption Agency
| Others |
| ACA | Antigomobilismo Circuito Das Aguas Paulista
| Others |
| ACA | Antique and Classics Automobile
| Others |
| ACA | Appalachian College Association
| Others |
| ACA | Apple Certification Alliance
| Others |
| ACA | Apples of California Agriculture
| Others |
| ACA | Application Center Administration
| Others |
| ACA | Applications of Computer Algebra
| Others |
| ACA | Area Cost Adjustment
| Others |
| ACA | Argentine Cricket Association
| Cricket |
| ACA | Arithmetic Comprehension Axiom
| Others |
| ACA | Arithmetical Comprehension Axiom
| Others |
| ACA | Arizona Commerce Authority
| Others |
| ACA | Arkansas Code Annotated
| Others |
| ACA | Arms Control Association
| Others |
| ACA | Army Contracting Agency
| Others |
| ACA | Army Control Authority
| Others |
| ACA | Arrowpoint Content Awareness
| Others |
| ACA | Asean Cosmetic Association
| Others |
| ACA | Asia Children's Assistance, LTD.
| Others |
| ACA | Asian Communication Awards
| Others |
| ACA | Aspect Camera Assembly
| Others |
| ACA | Assembly Constitutional Amendment
| Others |
| ACA | Associate Chartered Accountant
| Others |
| ACA | Associate of the Institute of Chartered Accountants in England and Wales
| Others |
| ACA | Associate of the Institute of Chartered Accountants in Ireland
| Others |
| ACA | Association Canadienne de l'Autobus
| Others |
| ACA | Association Canadienne des Automobilistes
| Others |
| ACA | Association of Canadian Advertisers
| Others |
| ACA | Association of Canadian Archivists
| Others |
| ACA | Association of Chinese Americans
| Others |
| ACA | Association of Consultant Architects
| Others |
| ACA | Associazione Collaudatori di Automobili
| Others |
| ACA | Asynchronous Communication Adapter
| Others |
| ACA | Atacama Compact Array
| Others |
| ACA | Atelier de Construction Automobile
| Others |
| ACA | Atlanta College of Art
| Others |
| ACA | Attache Commercial Automobile
| Others |
| ACA | Audio Compression Algorithm
| Others |
| ACA | Audio Content Architecture
| Others |
| ACA | Austin Cycling Association
| Others |
| ACA | Australian Clan Alliance
| Others |
| ACA | Australian Cloggers Association
| Others |
| ACA | Australian Corvettes Association
| Others |
| ACA | Australian Cricketers Association
| Others |
| ACA | Austrian Cricket Association
| Cricket |
| ACA | Auto Care Association
| Others |
| ACA | Auto Club Altena
| Others |
| ACA | Auto Consumer Alliance
| Others |
| ACA | Auto Contingent Allegiance
| Others |
| ACA | Auto Crime Association
| Others |
| ACA | Autobody Craftsman Association
| Others |
| ACA | Automatic Channel Assignment
| Others |
| ACA | Automatic Circuit Assurance
| Others |
| ACA | Automatic Component Activation
| Others |
| ACA | Automatic Conference Arranger
| Others |
| ACA | Automobil Club d'Andorra
| Others |
| ACA | Automobile Club Albania
| Others |
| ACA | Automobile Club Ardennais
| Others |
| ACA | Automobile Club Association
| Others |
| ACA | Automobile Club d'Aix
| Others |
| ACA | Automobile Club d'Alsace
| Others |
| ACA | Automobile Club d'Auvergne
| Others |
| ACA | Automobile Club of America
| Others |
| ACA | Automobiles de la Cote d'Azur
| Others |
| ACA | Automotive Career Academy
| Others |
| ACA | Automotive Club Alliance
| Others |
| ACA | Automotive Composites Alliance
| Others |
| ACA | Automotive Consumer Advocates
| Others |
| ACA | Automotive Corporation of America
| Others |
| ACA | Automovil Club Alicante
| Others |
| ACA | Automovil Club Argentino
| Others |
| ACA | Automovil Club de Almeria
| Others |
| ACA | Avanade Connected Architectures
| Others |
| ACA | Avid Customer Association
| Others |
| ACA | Awassa College of Agriculture
| Others |
| ACA | Awfully Clever Accountant
| Others |
| ACA | Canadian Archaeological Association
| Others |
| ACA | Project Manager Workbench Project file
| Others |